When navigating directories, every now and then pushd . and popd just aren't sufficient.
When directory structures tend to become quite deep, I get really annoyed with typing change-directory’s and wish I had some bookmarks.
That's why some time while ago I created a simple tool for usage within (GNU) screen:
CTRL+X pops up a menu for selecting common directories and files ("bookmarks"!).
This makes switching between those long directory structures a lot more pleasant !

Use in screen with C-x

Choosing a directory in the menu opens it in a new screen tab. Choosing a
file opens a new menu which allows you to dispatch it to specific editors or
e-mail it (options currently all hardcoded in the source).

Installation

Most of the code is still from 2007, but these last two days I refactored the code a bit.
And added some build scripts. (Needless to say I didn't get to implementing all features I had in mind.)
It's all on github for download.

It installs /usr/local/bin/launcher and two helper bash scripts (/usr/local/bin/launch_scr.sh and /usr/local/bin/launch_scr2.sh).
You bind it to screen in your .screenrc with this line: bindkey ^x exec /usr/local/bin/launch_scr.sh.